分析化学参考答案(武大第四版)

1、第一章 定量分析化学概论1. 某矿石的最大颗粒直径为10mm，若其k值为0.1kgmm-2，问至少应采取多少试样才具有代表性?若将该试样破碎，缩分后全部通过10号筛，应缩分几次?若要求最后获得的分析试样不超过100 g，应使试样通过几号筛?解：(1) 根据经验公式mqkd2，故至少采取试样mq=0.1102=10kg(2) 要通过10号筛，d=2mm，应保留试样mq0.122=0.4kg将10kg的试样进行缩分：10()4 =0.625kg0.4kg可见需缩分4次方可满足要求 。 查表1-1，故应通过20号筛。2.用氧化还原滴定法测得feso47h2o中铁的质量分数为20.01%，20.03%

2、，20.04%，20.05%。计算：a.平均值；b.中位数；c.单次测量值的平均偏差；d.相对平均偏差；e.极差：f.相对极差。解：3.用沉淀滴定法测定纯nacl中氯的质量分数，得到下列结果：59.82%，60.06%，60.46%，59.86%，60.24%。计算：a.平均结果；b.平均结果的绝对误差；c.相对误差；d.中位数；e.平均偏差；f.相对平均偏差。解：5.某试样中含mgo约30%，用重量法测定时，fe3+产生共沉淀，设试液中的fe3+有1%进入沉淀。若要求测定结果的相对误差小于0.1%，求试样中fe2o3允许的最高质量分数为多少?解： 设试样fe2o3中允许的最高质量分数为x%

3、6.某含cl-试样中含有0.10%br-，用agno3进行滴定时，br-与cl-同时被滴定，若全部以cl-计算，则结果为20.0%。求称取的试样为下列质量时，cl-分析结果的绝对误差及相对误差。：a.0.1000 g;b.0.500 0 g;c.1.000 0 g。解： 7. 某试样中含有约5%的s，将s氧化为so,然后沉淀为baso4。若要求在一台灵敏度为0.1mg的天平上称量baso4的质量时可疑值不超过0.1%，问必须称取试样多少克?解：8.用标记为0.100 0 moll-1hcl标准溶液标定naoh溶液，求得其浓度为0.101 8 mol.l-1，已知hcl溶液的真实浓度为0.099

4、 9moll-1，标定过程中其他误差均较小，可以不计，求naoh溶液的真实浓度。10. 有0.098 2 moll-1的h2so4溶液480ml，现欲使其浓度增至0.100 0moll-1。问应加入0.500 0 moll-1的h2so4溶液多少毫升?13. 欲配制na2c2o4溶液用于在酸性介质中标定0.02 moll-1的kmno4溶液，若要使标定时，两种溶液消耗的体积相近。问应配制多大浓度的na2c2o4溶液?配制100ml这种溶液应称取na2c2o4多少克?(2)配制100ml这种溶液称取 m na2c2o40.050.1126.077g14. 含s有机试样0.471 g，在氧气中燃烧

5、，使s氧化为so2，用预中和过的h2o2将so2吸收。全部转化为h2so4，以0.108moll-1koh标准溶液滴定至化学计量点，消耗28.2ml。求试样中s的质量分数。15. 将50.00ml 0.100 0moll-1ca(no3)2溶液加入到1.000 g含naf的试样溶液中，过滤、洗涤。滤液及洗液中剩余的ca2+用0.050 0 moll-1edta滴定，消耗24.20ml。计算试样中naf的质量分数。18. 不纯sb2s3 0.251 3 g，将其在氧气流中灼烧，产生的so2通入fecl3溶液中，使fe3+还原至fe2+，然后用0.020 00moll-1 kmno4标准溶液滴定f

6、e2+，消耗kmno4溶液31.80ml。计算试样中sb2s3的质量分数，若以sb计，质量分数又为多少?19. 已知在酸性溶液中，fe2+与kmno4反应时，1.00mlkmno4溶液相当于0.111 7g fe，而1.00ml khc2o4h2c2o4 溶液在酸性介质中恰好与0.20ml上述kmno4溶液完全反应。问需要多少毫升0.200 0moll-1naoh溶液才能与上述1.00mlkhc2o4h2c2o4 溶液完全中和?(根据武汉大学第四版教材各章习题内容撰写,仅供参考)(根据武汉大学第四版教材各章习题内容撰写,仅供参考)第五章 重量分析和沉淀滴定法(根据武汉大学第四版教材各章习题内容

7、撰写,仅供参考)(根据武汉大学第四版教材各章习题内容撰写,仅供参考)(根据武汉大学第四版教材各章习题内容撰写,仅供参考) acknowledgements my deepest gratitude goes first and foremost to professor aaa , my supervisor, for her constant encouragement and guidance. she has walked me through all the stages of the writing of this thesis. without her consistent and

8、 illuminating instruction, this thesis could not havereached its present form. second, i would like to express my heartfelt gratitude to professor aaa, who led me into the world of translation. i am also greatly indebted to the professors and teachers at the department of english: professor dddd, pr

9、ofessor ssss, who have instructed and helped me a lot in the past two years. last my thanks would go to my beloved family for their loving considerations and great confidence in me all through these years. i also owe my sincere gratitude to my friends and my fellow classmates who gave me their help

10、and time in listening to me and helping me work out my problems during the difficult course of the thesis. my deepest gratitude goes first and foremost to professor aaa , my supervisor, for her constant encouragement and guidance. she has walked me through all the stages of the writing of this thesi

11、s. without her consistent and illuminating instruction, this thesis could not havereached its present form. second, i would like to express my heartfelt gratitude to professor aaa, who led me into the world of translation. i am also greatly indebted to the professors and teachers at the department of english: professor dddd, professor ssss, who have instructed and helped me a lot in the past two years. last my thanks would go to my beloved family for their loving considerations and great confidence in me all through these years. i also owe my